CANADIAN GROUP. . 393 



guste expanse, reflexo, umbilicum (profundum et subito angu- 

 latiin excavatum) baud attingente. Diam. maj. tin. 5; 

 alt. 2. 



06,9. H. discobolo, ShuttL, affinitate proxima, sed multo 

 minor, magis tennis, ac magis opaca, densius et multo minutius 

 costulato-striata, necnon umbilico subminore et subminus 

 evidenter spiraliter visibili. 



H. affictce, Fer., ab ins. Palma, statura umbilicoque mino- 

 ribus, forsan magis affinis ; sed differt, inter alia, testa multo 

 minore, magis tenui, necnon crebrius minutiusque striata. 



Habitat Gromeram ; in statu emortuo necnon semifossili, 

 juxta Hermigua, collegit Rev. K. T. Lowe. 



Twelve examples of a Helix which are now before me, and 

 which were taken by Mr. Lowe, in a dead and imperfectly sub- 

 fossilized state, near Hermigua, on the western side of Gromera, 

 are clearly allied, in their suddenly and angularly scooped-out 

 umbilicus, general contour, and the exact number of their 

 volutions, to the H. discobolus, of that same island, as well as 

 (and perhaps more conspicuously so) to the H. afficta of Palma ; 

 nevertheless it is quite impossible to affiliate them with either, 

 their very much smaller stature and narrower umbilicus, 

 particularly (in both of these respects) as compared with the H. 

 discobolus, being quite sufficient, even of themselves, to warrant 

 their separation. But, in addition to these two discrepancies, 

 their shell is much thinner and more fragile than in either of 

 those species, and their surface is very much more densely and 

 minutely striated. Whether the H. gomerce, however, is an 

 undoubted member of the present fauna I can scarcely decide ; 

 but since some of the examples (although bleached) are com- 

 paratively fresh and of a pale corneous hue, I am inclined to 

 think that it can hardly be said to have passed wholly away. 

 Others, nevertheless, seem to be as completely ' subfossilized ' as, 

 at any rate, many of the Helices which are usually denned as 

 having been found in that condition. 



Helix discobolus. 



Helix afficta, d'Orb. [nee Per., 1821], in W. et. B.Hist. 66. 



t. 3. f. 24-26 (1839) 



discobolus, ShuttL, Bern. Mitth. 290 (1852) 

 Pfeiff., Mon. Hel. iii. 643 (1853) 



Mouss.,Faun. Mai. des Can. 66 (1872) 



Pfeiff., Mon. Hel. vii. 296 (1876) 



Habitat Gromeram ; in collibus aridis saxosis apricis juxta 

 San Sebastian, vulgaris. 



This is the largest of the Canarian members of the present 



